Jeff Thanks for the info. But I'm having a small problem. I went to the sight you linked but there is something I don't understand. The Lasorb link on there site will not work, only the one for red but the two blue links are broke and will not come on for the information. So I don't know which one is for 445NM. How did you do that? Did you turn it on yet? Thanks Jerry

There are 2 ways to select lasorbs. If the selection does no open up for the Blue ones on the driver page, select the lasorb button on the top of the page. For a 445nm LD you need the L44-683-X, not the Blue Ray one. Both pages seem to be working for me.

Now on both of my machines I use a MA3 shaft encoder to vary the 0-5 analog modulation voltage to the modulation input on the Flexmod driver. It requires another axis motor to rotate it, or you can drive it from the Z axis like on my mini engraver. If the drive ratios are setup properly, the Z axis does not move enough to effect the focal point.

My Son and his hobby I tried a little idea to see what would happen. The camo on the frame edges is a separate burn, the frame is angled high at focus, on the top, low below focus at the bottom and it did what I thought it would do. Its to late to change it now but it is a neat effect. It took about 8 hrs. to cut it, about 6.5 hrs. to burn it. and another day to build the frame. I used PEP4 423 beta horizontal. I am still using 50 ipm My next build I will try 65 ipm this seems a little dark. I'll just keep twisting things till it looks better. Thanks Jerry Jeff thanks again for the help.

Maybe you would want to consider implementing the laser diode on your CNC router so you will eliminate the alignment issue on your two processes. Rotary engrave then laser engrave it afterwards. A cap on the laser lens when rotary engraving to keep out the dust. I made mine so I can slip out the spindle and slip in the laser so the centers would be the same. In theory it should work, but I have not tried it yet.

Did this one today of a famous author. Maybe someone here can recognize him. The original image was small and low res, so I did the best I could to make it larger and edit it for engraving. Ran it at 230IPM with a 30% VFR at half power and a .004" PR.

Jeff Did you do that with your duel diode setup? Did you do that with PEP4 beta at 45 Deg.? I don't know the author. How can you run that fast (I'm not close)??? What is the size of the work you did. Good job! And I figures out how to align the two machines. I cut a profile on the router on the picture and laser a rectangle around a plywood base piece that is in my laser and align them. Than I just check it with johns program and do an edge around the work at 0. It is a lot better. I think the problem now is more in the software. I do my photo work with Corel Paint Shop Pro. The router work with BobCad-Cam. and the laser with PEP4 I crop with the photo software and if I'm not real careful it will move off a few pixels It will change the photo size and it rounds off the dimensions different. I think. Thanks again Jerry

Jerry, That picture is about 15 years (or more) old . I had forgotten about it. It was posted on my business web site (http://home1.gte.net/crcitser/ccs.htm). When we shut down our little consulting firm and retired, I discovered that Verizon had changed to new web hosting software, and I was locked out from changing or deleting the old site. I guess it will be up forever unless Verizon itself were to shut down completely. I tried for months to get them to help me delete the site, but they are not a very customer friendly company.

Now, the reason you can't run as fast as Jeff or I is because you have to use TTL mode with your CO2 controller. When you set up an analog laser diode, your speeds will pick up some. This is just they way gcode works, and why the commercial laser machines use different software. Probably with a single diode like I have, you should be able to run between 80 to 120 ipm, depending upon the wood/material you are engraving, and the power of your diode. With Jeff's monster, the mechanics of his machine prevent him from running faster, but I won't be surprised to see him improve that in the future :).

John A couple of those HA HAs are mine now that I know what that was all about. In that link you sent me ( Analog Laser Diode Setup) you have some information on (DAC) by Dave Gabry and a small addition to it by you. Looking it over I am having a bit of a problem figuring it out. I am not saying it isn't right I am saying I am a little slower than most electricians. I am a lot better at lawn mowers and vacuum cleaners. Looking at the part list I am unable to tell where his stops and your addition starts. There seems to be more parts on the schematics than the list. The components that you added, was it added into Dave's or was Dave's modified with only the addition of the 10 K ohm 15 turn Pot. Why does the counter need to be reset? When would you do this? What do you think about using the air from my compressor on the machine for cooling the laser diode instead of another fan? And last for now, Will I need another MA meter? Thank you Jerry

Jerry, I think you'll end up with 3 extra resistors, otherwise the parts count is correct to the schematic. I'm not sure why, but it may be because Mouser has a minimum order of 10 resistors per value.

The parts I added are in addidion to Dave's original parts. Dave didn't use them, but I think it made adjustments to the 0 to 5 v signal more accurate. The output signal from Dave's DAC goes to the input of the parts I added.

When first powered up, the DAC counter and output will be in an indeterminate state, so pushing the reset switch is needed to make sure the counter is properly set to zero with a zero input from Mach3. With Mach3 running, and the laser diode control axis set to zero, power on the DAC and momentarily push the reset switch.

Compressed air should work for cooling, but it is more expensive to generate than with a fan. I think builder's choice in this. You will also need air to blow smoke away from the diode lens.

I tried a 0 to 10 amp meter first, but it was not as sensitive as I wanted, so I use a 0 to 2 amp meter. Again, this is your choice. Be aware that with laser diodes, just going over the max. recommended current even a little bit can shorten their life considerably. I do not know how much safety factor is included in their specifications. Be sure you know the maximum current allowable for the diode you use. Not all 445 diodes are the same.

Now, about power supply selection. Both Jeff and I have burned out several diodes (ouch! ), and in my case I am absolutely sure it was because I used the wrong power supply. I now will not use any power supply for laser diodes other than a PC power supply, and I make sure it is not used to power anything else, especially stepper motors and drivers. Other powers supplies may work, but many may not be as well regulated and filtered as a PC supply.

John I am wondering about the Pots. There are three in the schematics pictured and only one listed. 1 Bios, 1 Gain and on Dave's at the modulation input. There all 10K ohms but only 1, 15 turn, is on your listing. I'm getting ready to order this and was just not sure. I already had a PC power supply ready to go one of the 5v outputs to run the CO2 and switch it to run the Diode. Do you think it would be okay to do that? There is a relay for the Mach3 for M3 and M5 and I could switch it after this point to run one or the other Laser, (I think). Would the amp gauge be wired into the (- ) from the diode? That is just a guess, it's all new to me but it will not be new to much longer. Thanks again for all your help Jerry

Jerry, If you build both circuits, you need 3 pots. Either ten or fifteen turn pots will be OK. Use what you can get. Any switching should be done on the power input sides of the DAC and laser driver. DO NOT put switches or meters in the leads from the driver to the laser diode. It is risky and could lead to burning out the LD. Put the meter in the + power lead to the laser driver, and it will read accurately enough. The driver itself will draw minimal current compared to the LD, so will not affect the LD current reading. JohnI paint with a blue light beam.

John is correct about running TTL vs analog. How I was able to get my blended feedrate so high is, change my ratios/pulleys around so I could lower the steps in the motor tuning. With lower steps, I was able to increase the feedrates and acceleration which increased the blended feedrates. I needed this speed because of the intense burning power my dual laser diode build outputs. Your new single laser diode build should be able to run and engrave the same speed as John's setup.

I sure learned my lesson by not using a lasorb. Watch this video.

The diode I posted a link to (me and John uses) has a built in ESD, but it will not stop surges from un-regulated power supply's or mysterious charges on machine frames like happened to us twice (X 2 diodes each time)

I also want to say the MA3 shaft encoder option is an easy setup. No circuit to build, but does require another axis, motor, timing belt and pulleys and a bracket to mount them on. On the servo machine, I just used a piece of aluminum angle. There is a picture of it in this thread somewhere. 5V in (USB) 0-5V out based on a shaft rotation. Also there are some advantages to it. Adjusting the power range is easy by changing the steps in Motor Tuning for a 4th axis motor that is driving it. Also it allows you to set your start to burn level (Zero) on different materials and have 256 more steps from there. This is nice when you set a safe height for the edges to back off the power above zero to eliminate edge burning. That is a new option in John's program.

With Dave's DAC or the MAX5451 digital potentiometer circuit, your limited to 256 steps and if the code goes out of that range, it gets lost where it's at.

John I ordered the parts for the DAC and your add on and I missed a resistor. There is a 33K ohm resistor at the TLV272 number 3 + terminal to the wiper on the 10K ohm pot (gain). What is the Watt rating for that resistor? Also I do not know if this is something I should worry about but the pin numbers of the TLV272 on your drawing of the added part are not the same as the drawing on the DAC for the TLV272 (pins #2 and #3 are reversed). I ordered the 10 turn pots because the 15 turn ones are quite pricy. I will have to Wait until payday next month to buy my laser diode. I do have plenty to do until I get it but I can't wait. Thanks Jerry

Hozzáadva (2013-11-07, 20:00)---------------------------------------------John I started playing with some mirror this morning and I found out that I am able to etch the back part of the mirror. It takes a lot of heat and I slowed way down to mark it but it will work. I am sure I will need to do a lot of experimenting to get it right but it will come. I think! Do you know where I may be able to find out information on the procedures? I have started looking through the forum but there is so much. I thought I read something in one of your manuals but I do not seem to be able to find it. I would like to study a bit before I actually start. I see that the bad parts I will not be able to help heat my shop with. My mistakes now can go into the fire place. Thanks Jerry